I made a mob farm really early into my survival playthrough, before I even made my wheat farm. And I think more people should do the same because the benefits are really great! Building it isn’t hard but it takes a long time and a LOT of blocks. Here is why you should build it though
- Bow and arrows, since skeletons drop bows and arrows you will have so many stacks of arrows and you will probably never need to craft one. Also, the mobs can hold enchanted bows and I got a bow with power 2 and punch! And the bows usually drop with lots of damage, but you can craft them together to make a less damaged one, but for enchanted bows you need an anvil to repair it
- You also get lots of gunpowder. If you have lots of sand then you can make LOTS of TNT. I used about 18 blocks of TNT in deepslate and got 21 diamonds! 20 blocks of TNT would need only 100 gunpowder, which isn’t an issue with a mob farm!
- Here are most of the resources you can get: string, spider eye, rotten flesh, bones, arrows, bows, carrots, iron ingot, potatoes, gunpowder, feathers, raw chicken, armor, swords. You will also have so much bonemeal you can grow a farm in no time
Keep in mind that the mob farm slows down at night, so I suggest putting a bed up there so when it’s night you sleep. I also didn’t see a difference in the amount of mobs spawning depending on the difficulty, but the difficulty does make them spawn with more armor.
building a mob farm for xp is pointless. just build a mob farm that you can afk and build a gold or enderman farm for xp. iron farm in spawn chunks should be within the first 30ish days